The invention discloses a drug for a stable stage of chronic obstructive pulmonary diseases and a preparation method thereof. The medicinal effective components are composed of radix astragali preparata, sun-dried ginseng, bulbus Lily, cortex lycii, herba ephedrae preparata, semen armeniacae amarum, rhizoma atractylodis, gecko, bulbus fritillariae thunbergii, seeds of snake gourds, radix trichosanthis, poria cocos, dried orange peels, radix platycodi, rhizoma pinelliae preparata, radix glycyrrhizae preparata, rhizoma alismatis, cortex moutan and radix paeoniae rubra. The drug has the effects of tonifying deficiency (invigorating qi-yin of the lung and invigorating qi of the spleen and kidney), eliminating phlegm, removing dampness, facilitating diuresis, promoting blood circulation, removing blood stasis, nourishing yin, clearing away internal heat, ventilating the lung and unclogging the viscera. The drug can be used in the stable stage of chronic obstructive pulmonary diseases, improve immunity, reduce the frequency of acute aggravation induced by infection, improve the lung function, promote oxygenation, control the disease progress and relieve cough, expectoration, asthma, anddyspnea.